Experiences with a Commercial Ecdis
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International Hydrographie Review, Monaco, LXVII(2), July 1990 EXPERIENCES WITH A COMMERCIAL ECDIS by H. LANZINER, (*), D. MICHELSON (*), S. LACHANCE (**) and D. WILLIAMS (***) Abstract The integration of accurate positioning and electronic charts provides an extremely valuable tool to the mariner when navigating under hazardous conditions. This paper describes the experiences of two organizations in Canada who work under such conditions. On the St. Lawrence River, the Canadian Coast Guard is using the PINS 9000, a commercial ECDIS, for ice breaking chores with few, if any, other aids and has demonstrated operational savings. Marine Atlantic, Inc., uses the same system for ferry navigation into and out of Port aux Basques, Newfoundland, where it not only assists in meeting a tight schedule, but also enhances safety when operating in difficult conditions. EXPERIENCE WITH A COMMERCIAL ECDIS 1. Introduction During the past fifty years, mariners have adopted a host of electronic navigation and positioning aids in a bid to make navigation safer and more efficient. Numerous systems designed for collision avoidance (radar, VHF radio telephone) or enroute navigation (LORAN-C, GPS) are either currently available or, as in the case of GPS, currently being deployed. However, while various studies and specifications that have been produced in recent years demand that ships maintain a high degree of position accuracy while operating in confined waterways and harbours, the manual position plotting methods that are still commonly used today are not able to display this information without incurring significant delays and the possibility of human error. As a result, the position shown on the paper chart represents the ship’s historical position rather than its (*) Offshore Systems Ltd., North Vancouver, British Columbia, Canada. (**) Canadian Coast Guard, Ottawa, Ontario, Canada. (***) Marine Atlantic, Inc., Moncton, New Brunswick, Canada current position. This delay effectively negates recent efforts to enhance the safety of vessels and prevent groundings by providing highly accurate position data through the use of microwave transponders, radar-assisted precise navigation systems, and the Global Positioning System (GPS). By combining hydrographic chart data with position and orientation infor mation obtained from the ship’s gyrocompass and electronic navigation aids onto a video display in real time, Electronic Chart and Display Information Systems (ECDIS) provide a means to overcome many of the limitations of paper charts that are encountered in operational situations. By continuously and automatically plotting the current position, course, and track of one’s own vessel relative to the nearby coastline, navigation hazards, and one’s intended track in real time, electronic charts permit mariners to make optimal use of modem precise vessel positioning systems. No longer burdened by the repetitive (and potentially fatiguing) task of manual plotting, watchkeepers can devote more time and attention to other matters concerned with the safe passage of the ship. The PINS 9000 (Precise Integrated Navigation System) is a second gene ration commercial ECDIS that was introduced by Offshore Systems Ltd. (OSL), in 1985. During the past five years, PINS 9000 systems have been installed aboard a variety of ships including icebreakers, ferries, oil tankers, research vessels, and several Canadian and U.S. naval vessels. A representative summary of PINS installations is given in Table 1. Feedback from users has been very favourable. PINS has been described as ‘a master’s dream when you have to manceuver in a confined area with no visibility’ [1] and, ‘after the gyro and radar, ... the most useful instrument we have’ [2], PINS was designed to support both conventional navigation tasks in coastal and inshore waters and more demanding activities including pilotage in confined waters, ice breaking, marine surveying, ship manceuvering trials, and coordination of underwater operations involving use of both tethered and autonomous vehicles. In this paper, we consider experience accumulated by the Marine Atlantic, Inc. (which operates two PINS-equipped ferries on a route between North Sydney, Nova Scotia, and Port aux Basques, Newfoundland) and the Canadian Coast Guard (which operates six PINS-equipped icebreakers on the St. Lawrence River between Lac St. Pierre and Quebec City). Those features which have contributed most to the success of PINS in operational situations are identified and discussed. Directions for future development are considered. 2. The Need for Electronic Charts The speed, direction, and position of the vessel relative to navigation hazards is of primary concern to the master or pilot when guiding a vessel through coastal or inshore waters. Delays in processing incoming data into a form where this information can be extracted are critical. In the minute that it might take to transfer incoming data to a paper chart (and it would often take longer), a vessel moving at only 10 knots will have travelled over 300 metres. A vessel moving at 15 knots will have travelled a quarter nautical mile! Thus plotting on a paper chart can hardly be acceptable when most harbour and channel navigation plans [3, 4] require that large ships maintain positioning accuracy to between 8 and 20 metres. Table 1 — Partial Summary of PINS 9000 Installations Name Length Grt Year Client Application HMCS Cormorant 245 fl 2350 1989 Dept, of National Route Survey/ Canadian Navy Defence Seabed Surveillance CFAV Lady Alexandria 1067 1989 Dept, of National Route Survey/ CFAV Lady Joyce 191 ft Defence Seabed Surveillance Canadian Navy U.S. Navy Tracking 1989 David Taylor Labs, W A Underwater Tracking Station of Submarines CGCS Tracy 167 ft 963 1989 Canadian Coast Guard, Ice breaking and Laurentian Region Buoy Tending M/V R. Hal Dean 44840 1988 Chevron International Channel Navigation 760 ft MV Charles B. Renfrew Shipping Company, and Docking of San Francisco, CA Tankers R/V Oceanus 177 ft 297 1988 Woods Hole General Navigation Oceanographic Insti tution, Woods Hole, M A USS Ortolan, ASR 22 251 4570 1987 The Charles Stark Submarine Rescue U.S. Navy Draper Laboratory, Operations. Sub Cambridge, M A marine and Surface Ship Tracking (Atlantic) M/V Atlantic Freighter 495 ft 5466 1987 Marine Atlantic Channel Navigation North Sydney, N.S. and Docking CCGS Montmagny 137 ft 492 1987 Canadian Coast Guard, Icebreaking and CCGS Sir Wilfrid Laurier 257 ft 3812 Laurentian Region Buoy Tending CCGS Norman M. Rogers 275 ft 4299 CCGS Pierre Radisson 296 ft 5910 CCGS Des Groseilliers 296 ft 6098 Vancouver Port Office — 1986 Van. Port Corporation Harbour Management USS Pigeon, ASR 21 251 4570 1986 The Charles Stark Submarine Rescue U.S. Navy Draper Laboratory, Operations. Subma Cambridge, MA rine and Surface Ship Tracking (Pacific) M/V Researcher 83 ft 128 1986 International Submarine Tracking Display of Engineering Underwater Vehicles and Surface Vessel M/V Chi-Cheemaun 347 ft 6991 1986/ Ontario Northland Channel Navigation 1985 Transportation, Owen and Docking Sound, Ontario M/V Caribou from 587 ft 27213 1986/ Marine Atlantic, Channel Navigation M/V Atlantica 1985 North Sydney, N.S. and Docking CFAV Endeavour 236 ft 1560 1985 Defence Research MCM Operations Canadian Navy Establishment Pacific and Seabed (2 systems) Surveillance Much of the power of the electronic chart (and the feature which distinguishes them most from conventional chart plotters) comes from their ability to process data fro m a variety of sources and to detect and graphically show relationships between the data. This capability extends far beyond the use of a Kalman filter to integrate position data from various navigation aids and to generate an error ellipse on the chart display as an indication of the fix quality. For example, since an electronic chart combines one’s position with chart information, it can be programmed to automatically warn of proximity to underwater hazards such as reefs or rocks. It would be extremely difficult (if not impossible) to detect such hazards using conventional collision or grounding avoidance systems such as radar or depth sounders. When failure to execute the planned route (as suggested by significant deviations from expected course, speed, cross-track distance, or water depth) is detected, the electronic chart can be programmed to generate various visual and audible alarms. By permitting one to overlay radar imagery onto the electronic chart display, the next generation of ECDIS will considerably ease the task of interpreting the radar display and distinguishing ship targets from land returns. These capabilities, coupled with a carefully designed and non-intrusive user interface, will enable electronic charts to play an effective and important role in the prevention of ship groundings and collisions during the 1990’s. Some have described ECDIS as the most revolutionary advance in coastal navigation and pilotage since the introduction of the paper chart several hundred years ago. In situations where vessels are required to navigate through narrow and poorly marked channels during conditions of poor visibility, the need for electronic charts in combination with precise positioning systems has been both obvious and immediate. Examples considered in this paper include large ferries using the harbour at Port aux Basques, Newfoundland, where poor weather can reduce visibility to near zero during critical phases of the harbour approach and Lac St. Pierre on the St. Lawrence River south-west